Spark-plug



A. SCHMlDT.

SPARK PLUG;

APPLICATION men SEPT 25! 1918 1,352, 1 48. Patented. Sept 7, 19135.

W I TNESS:

1 N VEN TOR.

A I TORNEY plug and the central eleetrode with SAN, ASSIGNOR Tu GAIN, A CORPORATION QF IVLICHIG' PATENT CHABIPIOII I ABILPLUG.

Application filed September 25, 1913.

ile it known that imucirr fhjniuio'r, a eilixen ol' the l uiled States and resident ol l lintn (lenesee eounty, State of iliiehipjau, have invented eertain new and usel'ul lir- ;uormnenls in 'lePlug ot \vhir'h the l'ollowiu r is a sperilieation.

The invention relates to ilnprovenlents in spark pl' and more partieularly to the means for ell rtinp' a seal lwtwren an insulator and a ventral electrode supported therein.

The objeets ol the invention are in de vise a simple and durable means tor elteetually sealing the joint between the ventral eleetrode and the insulator. and to elleet sueh withrnit subjecting the parts to unneeessauv strain or continued str ,4.

'lheso and various other objeets will elearly a wear iron: the Following descrip- X A lion, talen in eonnertion with the aeeoinpanyhu: drawing whieh forms a part or" this smv'ilieatioir in the drawing l :ure 1 a side elevation ol a spark pllrfisnowing 1e upper portion lhereol broken away in sections to illus- 'lrate tl e inrention. and Fig. 2 is an elevation view of the upper portion of a spark the terunual nuts and Saling washers removed therefrom and partially in section.

Like numerals o l' reference indicate similar parts throughout the views.

Rel'errin g to the drawing, a spark pin shell ll) is shown having the insulator ll arranged therein and the eentral eleetrode l2 auehored in said insulahn' and projewtin; upwardly therel'ronn as eu:;lonnir in spark plug eonslruetion ol' the type shown it inust be understood that the parlieular eon struetiou ol' the shell or insulator is quite immaterial as concerns the presi'wnt invention, always providing the insulator has the Oltlil'lvtl? projecting upwardly there'l'roin and there isoeeasion to term a seal thereabout.

To tor-n1 the seal on the top or the insulator and about the eentral electrode 12, a eoinpression gasket 13, made of material such as asbestos provided, the same litting around the eleetrode and against the upper end of the insulator.

Next above the eompresion sealing;- washer 1% is arran, ;e h ha ving the under side thereof said washer l orine l eonnpecification of Le Jters Patent.

Serial No, 5255,57 1.

cave and the upper side thereof project 1 upwardly in triis't -oiiii:al shape as at 15, the central oriliee ol said washer and through whioh the eentral elem ode extends 'l'orining with said lii liowollii'al portion a v *ry thin upper edge is about said washer.

"i'he electrode 12 is rapped by a terminal nut l7, which is permanently seeur: l in plaee upon the upper end thereof and which may l e ol any desired tornn the one shown in the drawing being of spheriez 1 sh pe and ha ving the central threaded oritiee '1, with the blind end 1:) on the interior or said nut and said orii'iee 18 being flared slightly adjarent the open end to provide a eouieal s rtaee which fits over the upwardly ex tending? irusto eo11i-;-al portion of the nut l-l.

in assembling the part to make the seal ll lb upper end 01" th: eleetrode, the with the roinpres ible gasket is 3 firm onto the insulator by any suitable die or holding and the terminal nut is serewed into position whereby the. parts are held with the outer edge periphery oi the washer lirully seated upon the minpreseion gasketli-l, whereby praetieally a peripheral line contact is made about the gasket and the outer edge'the-reot firmly and evenly pressed down onto the top of the insulator l1, much more eti'eetively than would be the -ase it the washer 1% had a flat under side and pressed over the entire snriaee of the eoinpression gasket 13. In like manner the nut 17 as it is screwed down over the trustowonieal upper portion oi the washer i? will rea lily spin inwardly the thin metal and seal the same elleetually about the ventral elei-trode. A the same time the liared part of lheoriliee in the out will seat hselt firmly upon the outer taro ol' the trustowonieal upper end of the nut and very ei'leetively s al the joint thew-about eoineideut with the sea'lin; l' the joint be tween the nut and the insu :tor by n'ieans oil the con'ipression gasket 13 as above described.

Partieular mention is made of the manner in whieh the entire seal made with re spent to the materials usedi that is, the insulator is preferably made of porcelain and the seal between it and the nut l is made entirely by compression ineans vii out any rotation thereof, and eonsetuently Witnout stresses or rains upon tne poreelain insulator beyond; that which it can readily sustain, but where the nut is screwed onto It must also be noted that the electrode is very slightly spaced away from the orifice I in the insulator, whereby the tightening of the sealing members will in no manner cause any lateral stresses where the electrode projects out of the insulator, and in this manner not only is the seal more effectual but the insulator itself properly sup- )orted against accidental concussion.

While I'have described and will specifically claim what I deem to be a preferred embodiment of my invention, it will be obvi'ous to those skilled in the art that variouschanges may be made modifications and from the spirit and scope without departure thereof.

Having thus described I claim and desire to secure by Letters Iatent is:

1. In a spark plug, and an electrode secured therein and sealed at the protruding end thereof by a sealing member having a compression bearing against said insulator about the lower and outer periphery and against-said electrode about the upper and inner periphery thereof. 2. In a spark plug, the combination with an electrode and means for supporting the same in said plug, of a Washer about said electrode, and means for-forming a compression seal between the outer periphery of said washer and said supporting means and the inner periphery of said Washer and said electrode. I I

3. In a spark plug, an insulator having an electrode anchored therein and pro1ect- .ing there-above, a scaling washer of'substantially frustoconical shape having a concave lower face next said insulator and a tapered upper end next said electrode.

will

my invention, what,

an insulating element 4:. In a sparkplug, an-insulator having an electrode anchored therein andprojecting thereabove, a sealing washer of substantially frustoc'onical shape having a concave lower face next said insulator and a tapered upper end next said electrode, and means for seating said washeronto said insulator and electrode.

In a spark plug, an insulator having an electrode anchored therein and projecting thereabove, a gasket of compressible material about said electrode, a sealing washer about said electrode above said gasket and having a concave under surface, and means for seating sai washer to compress said gasket about the periphery thereof against said insulator, said seating and compressing means being permanently secured in place upon the free upper end of said electrode.

6. In a spark plug, an insulator having an electrode anchored therein and project ing thereabove, a gasket of compressible material about said electrode, a sealing washer about said electrode above said gasket and having a concave under surface, and an upperpart of substantially frustoconical form, and means for seating the washer to compress said gasket about the periphery thereof against said insulator and to seal between the upper end ofsaid washer and said electrode.

7 In a spark plug, an insulator having an electrode anchored therein and projecting t'hereabove, a gasket of compressible material about said electrode, a sealing Washer about said electrode above said gasket and having a concave under surface, and an upper part of substantially frustoconical form, and a nut threaded onto said electrode and compressing said washer and gasket.

8. In a spark plug, an insulator having an electrode anchored therein and project ing thereabove, a gasket of compressible material about said electrode, a sealing washer about said electrode above said gasket and having a concave under surface, and an upper part of substantially frustoeonieal form, and a terminaln-ut threaded onto said electrode and fitting-over the'frustoconical end of said washer to seal the same about said electrode and to compress said gasket and seal the same about said insulator.

In testimony whereof I atlix my signature.

' ALBERT SCHMIDT. 

